Alpha thionylaminoanthraquinone and process for making same



fiatented Aug. 23, 1949 2,4799% I ALPHA THIQNYLAMINQANTHBAQUI Q E ANDreo iiss. 5 Hans Z. Lecher, Plainfield, and Dale Raymond Eberhart,Bound. Brook, N. .I-., assignors to; American. Cyanamid Company, NewYork,

N. Y a corporation Y ihe No Drawing.

Application February. 5, 1947:,

Serial N 0. 725,136

elche namqeathred ineae i metered hr er us methods .1 eith c eet icneieeel re widely sed interva s. th a imation. te heriquinone alpha suiionicacid with ammonia under pressure This. methqa. While eq iqel qell eatefrom a ve y clis dra ae th the a ph emincanthraouinone produc d coatremaiti s. which ar ve y un esirable. o certa 2 .1

poses and are. also. if cult q remove- While impure alphaaminoanthraquinone may be used. for certain p rposes. h ence 9i th impurti s pre udes use as an nterm diate is: certa n valu ble dv stufis. F eam le yellow colorsof great comme cia importance may he iltained by hereact n or halo en. deri ativ s o 1,3,5-tr'1ezin s. such as cvanuric. cride, 0. h alpha aminoanthraquinone. The importance of these l r l s inthe unusual bri htness, HQW". ever, for example, when cvanuric hlo de racted. with alpha amino anthraq in ne contains me. the usual impurities,the desired bright green-.. yellow shade is seriously. dulled. This chane in shade renders the product unacceptable to the trade.

Because of the economy of production oi. alpha aminoanthraquinone by theamination oi the al-. phasulfonic acid, numerous attempts have been madein the past to remove the undesirable.im-, purities. These methods,however, have either been ineffective or very expensive and time.consuming, which has precluded their practical use. Qne example of. sucha method is fractional crystallization, which will not result insufiicient re.- moval of the impurity without involving excessive lossesor the crude alpha aminoanthraquinone. 1

According to the present invention the crude alpha aminoanthraquinone.is purified by trans: ormin t to lp a hionylaminoanthraqumone hyreaction with thionyl chloride, followed by fil-. ret c a d re n rationof t e urifie am ne,

hie v ee m n r quinen hes th 9 lowing formula:

12 Claims. (01. 250-373 ts or wh n: hlorid w h. woul e d. u if'a'solvent were employed which reacted with it. The process may beenected advantageously by refluxing the aminoanthraquinone and thionylchloride in the inert solvent, followed by hot filtration, preierablyin, the presence of decoloriaing material such as decolorizina carbon.

The filtrate which is free from the undesirable impurities and containsthe bright green-yellow thionylarninoanthraquinone, may be treated invarious. ways to. recover the. thionylarninoanthraquinon from it, forexample, evaporation pro: er r e iee i ece the th yl me mequ en is nrmal n used a e ii intermediate but is usually. first hydrolyzed to re;generate thealpha nc a at quinone, we have ou d hat a ve r fileien andece emieel F ee? se e -Q ds e is ion of he h avlem nei r ei aene. In sPrbees e amine compound is obtained directly in a pure form from thefiltrate by hydrolyzing with Water and acid. A particularly advan a eousmodifi a ion invo v s steam distillation o the or anic solvent, which mves the solv n hydroly es the. th onvle amino nthraqu non and produces awaters e.- p n ion of pure alpha aminoan hraquin ne. I is remarkable andunusual; that the solution of alpha thionylaminoanthraquinone can beused di-. rectly without isolation or removal of the solvent. forreaction with acid chlorides. such as cyanuric chloride to producedyestuffs and intermediates. For example, the yellow dye,2,4,6-(tri-alpha-anthraquinonylamino.) -1,3,5-,triazine, can be preparedby adding cyanuric chloride to a solution ofalphathionylaminoartthraquinone prepared in situ. The dye has the followingformula:

7 The organic solvent used in the present inven-. tion must not bereactive to thionyl chloride and o the mine, t m dis o he thieev amieqethr u ncn T a 1? us 519i 9. .9 9. 9

th thi erl h o i e Th s r st i t the so vents wh ch can be u ed s ewhat,but sti p rmit the employ i" e m u ti s which e not. react thechlorinated aliphatic hydrocarbons, such as carbon tetrachloride,ethylene chloride, acetylene tetrachloride, and the like, and aromatichydro carbons such as benzene, are typical examples. The above solventsare given as examples of the cheapest and most satisfactorymembers oftheir groups, and may be considered the preferred solvents.

The thionylaminoanthraquinone which is produced in the present processis itself a new chemical compound and is included as part of the presentinvention.

The invention will bedescribed in greater detail in conjunction with thefollowing examples, which are illustrative. 'All parts are by weight.

Example. 1

o N=S=O A mixture of 14 parts of impure alpha aminoanthraquinohe, 11parts of thionyl chloride, and about 250 parts of carbon tetrachlorideis refluxed until reaction is complete. About one part of decolorizingcarbon is added and the reaction mixture filtered. The bright orangefiltrate, upon cooling, deposits yellow crystals of alphathionylaminoanthraquinone. These crystals are filtered and washed withcarbon tetrachloride.

Example 2 A mixture of 67 parts of crude alpha aminoanthraquinone(preferably from the sulfonic acid), 57 parts of thionyl chloride, and450 parts of benzene is refluxed for 1 -2 hours. About one part ofdecolorizing carbon is added, and the reaction mixture is filtered. Tothe filtrate added about 20 parts of alcohol. The orangetan precipitateproduced is filtered and washed with benzene. This cake is suspended inwater, the benzene steamed out, and the hot slurry filtered and washedacid-free. The filter cake is dried, giving a high recovery of very purealpha aminoanthraquinone.

Example 3 1 7B &

A mixture of about 16 parts of crude alpha aminoanthraquinone(preferably prepared from the sulfonic acid by amination), 380 parts ofcarbon tetrachloride, and parts of thionyl chloride is stirred andrefluxed for three hours. The'mixture is cooled slightly, two grams ofdecolorizing carbon is added; and the stirring and refluxing continuedfor an additional 2 /2, 3 hours.

The reaction mixture is filtered while hot into another reaction vessel.7

To the nltered solution obtained as described above are added 3.8 partsof cyanuric chloride and 190 parts of phenol. The mixture is heated to110 C. and held at this temperature ior such a time as to allowsubstantially all the carbon tetrachloride to distill from the reactlon.The temperature is then raised to about C. and maintained for threehours. Alter cooling, about 2110 parts or, ethyl alcohol is added. Theslurry is filtered and the cake Washed with alcohol and dried. Theyellow dye is obtained in extremely high yieldand has dyeing qualitiesmuch superlor to those of the dye Irom uhpnrified aminoanthraquinone.This dye; when prepared irom alpha amlhoanthraquinone purified by ournew process is a pure green-yellow equal in shade-to that made from theintermediate after completepurificationby expensive and lengthy methodswhereas the unpurlfied alpha alnlnoanthraquinone gives a dye of a muchduller color.

We claim:

1. Alpha thionylaminoanthraquinone.

2. A process I01 the preparation of alpha thionylaminoanthraqulnoneWl'llCl'l comprises reacting alpha alnlhoahtnraqulnone with thionylchloride in an inert organic solvent at elevated temperatures.

A process according to claim 2 in which the alpha aminoanthraquinone isthe crude product obtained from the animation of the correspondinganthraqulhone sull'onic acid and the solvent used has low solvent powerfor the impurities present, and the reaction mixture is filtered hot andthe alpha thionylaminoanthraquinone recovered from the resultingfiltrate.

4. A process for purifying alpha aminoanthraquinone which comprisesreacting the impure alpha aminoanthraquinone with thionyl chloride at anelevated temperature in an inert organic solvent having good solventaction for alpha thionylaminoanthraquinone and low solvent action forimpurities, and filtering the reaction mixture and hydrolyzing thethionyl compound.

5. A process for purifying alpha aminoanthraquinone which comprisesreacting impure alpha aminoanthraquinone obtained by theamination of thecorresponding sulfonic acid with thionyl chloride at elevatedtemperatures in an inert organic solvent having good solvent action onthe thionyl aminoanthraquinone and low solvent action on the impurities,filtering the reaction mixture and hydrolyzing the alphathionylaminoanthraquinone.

6. A process for purifying alpha aminoanthraquinone which comprisesreacting impure alphaaminoanthraquinone obtained by the amination of thecorresponding sulfonic acid with thionyl chloride at elevatedtemperatures in an inert organic solvent having good solvent action onthe thionyl aminoanthraquinone and 'lOW solvent ac- REFERENCES CITED Thefollowing references are of record in the file of this patent:

6 FOREIGN PATENTS Number Country Date 268,592 Germany Dec. 20, 1913OTHER REFERENCES Michaelis Liebigs Annalen, vol. 274, pages 178-182(1893).

Anschutz et a1. Liebigs Annalen, vol. 493, page 242 (1932).

